S-91255A035 5/16"-18 x 1 3/4" ASTM F835 Steel Button Head Hex-Drive Screws

Key Features & Benefits at a Glance

• Exceptional corrosion resistance with black-oxide coating, extending service life in demanding industrial environments
• Superior tensile strength (120,000 psi) ensures reliable performance under high-stress applications and prevents fastener failure
• Precision Class 3A thread fit provides secure, vibration-resistant connections with minimal risk of loosening
• Rockwell C39 hardness rating delivers excellent wear resistance and maintains thread integrity through repeated use
• Hex drive design with 3/16" drive size enables quick installation and high torque application with standard tools
• Fully threaded UNC coarse spacing allows for faster assembly and stronger holding power in various materials
• Comprehensive regulatory compliance including ASME B18.3, ASTM F835, RoHS 3, and REACH ensures quality and environmental responsibility

Professional Applications & Engineering Value

These black-oxide alloy steel rounded head screws deliver critical performance advantages for industrial assembly applications where reliability is paramount. The combination of 120,000 psi tensile strength and Rockwell C39 hardness provides exceptional resistance to shear forces and material fatigue, making them ideal for heavy machinery, automotive components, and structural frameworks. The UNC coarse thread spacing ensures rapid installation while maintaining superior pull-out resistance in softer materials. The button head profile offers a low-profile finish that reduces snagging hazards while the black-oxide surface treatment provides essential corrosion protection in environments exposed to moisture and chemicals. These hex drive screws are engineered to withstand vibration and dynamic loads common in manufacturing equipment and industrial assemblies.

Specification Summary & Compliance

This 5/16"-18 x 1-3/4" rounded head screw features precision Class 3A thread fit with UNC coarse thread spacing and full threading along the entire shank length. Manufactured to exacting standards including ASME B18.3 and ASTM F835 specifications, ensuring dimensional accuracy and consistent performance. The product maintains compliance with RoHS 3 (2015/863/EU) restrictions on hazardous substances and REACH (EC 1907/2006) environmental standards, meeting current regulatory requirements for industrial applications.